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Articles
Current
Special Feature Articles - Most Recent
Special Features
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Open Access
The appearance and duration of the Jehol Biota: Constraint from SIMS U-Pb zircon dating for the Huajiying Formation in northern China
Saihong Yang
,
Huaiyu He
,
Fan Jin
,
Fucheng Zhang
,
Yuanbao Wu
,
Zhiqiang Yu
,
Qiuli Li
,
Min Wang
,
Jingmai K. O'Connor
,
Chenglong Deng
,
Rixiang Zhu
, and
Zhonghe Zhou
PNAS
June 23, 2020
117
(25)
14299-14305;
first published June 8, 2020.
https://doi.org/10.1073/pnas.1918272117
You have access
Fundamentally different global marine nitrogen cycling in response to severe ocean deoxygenation
B. David A. Naafs
,
Fanny M. Monteiro
,
Ann Pearson
,
Meytal B. Higgins
,
Richard D. Pancost
, and
Andy Ridgwell
PNAS
December 10, 2019
116
(50)
24979-24984;
first published November 25, 2019.
https://doi.org/10.1073/pnas.1905553116
You have access
Dome-headed, small-brained island mammal from the Late Cretaceous of Romania
Zoltán Csiki-Sava
,
Mátyás Vremir
,
Jin Meng
,
Stephen L. Brusatte
, and
Mark A. Norell
PNAS
May 8, 2018
115
(19)
4857-4862;
first published April 23, 2018.
https://doi.org/10.1073/pnas.1801143115
You have access
Insight into the growth pattern and bone fusion of basal birds from an Early Cretaceous enantiornithine bird
Min Wang
,
Zhiheng Li
, and
Zhonghe Zhou
PNAS
October 24, 2017
114
(43)
11470-11475;
first published October 9, 2017.
https://doi.org/10.1073/pnas.1707237114
You have access
On transient climate change at the Cretaceous−Paleogene boundary due to atmospheric soot injections
Charles G. Bardeen
,
Rolando R. Garcia
,
Owen B. Toon
, and
Andrew J. Conley
PNAS
September 5, 2017
114
(36)
E7415-E7424;
first published August 21, 2017.
https://doi.org/10.1073/pnas.1708980114
Open Access
The presumed ginkgophyte
Umaltolepis
has seed-bearing structures resembling those of Peltaspermales and Umkomasiales
Fabiany Herrera
,
Gongle Shi
,
Niiden Ichinnorov
,
Masamichi Takahashi
,
Eugenia V. Bugdaeva
,
Patrick S. Herendeen
, and
Peter R. Crane
PNAS
March 21, 2017
114
(12)
E2385-E2391;
first published March 6, 2017.
https://doi.org/10.1073/pnas.1621409114